3D Bioprinting for Personalized Medicine: Advances, Challenges, and Future Directions.

Due to the shortage of donors and the immune rejection of patients, the shortage of tissues/organs is a major challenge in the medical field. Since the development of regenerative medicine, the exploration from constructing disease models in vitro to the repair, regeneration, and replacement of organs in vivo has never ceased. However, few technologies can replicate complex tissue structures and cell spatial heterogeneity. As a biological manufacturing method, three-dimensional (3D) bioprinting has developed rapidly and can deposit biomaterials and cells in a 3D controlled space with unprecedented accuracy. Compared with traditional tissue-engineering methods, 3D bioprinting can create highly complex 3D structures with the assistance of computer-aided design software and multiaxis motion platform hardware. In addition, 3D bioprinting can directly use medical imaging data to create patient-specific anatomical models and tailor organs or tissues for different patients. This review introduces the emerging materials and technologies for 3D bioprinting and focuses on the concept verification of 3D bioprinting and its applications in the fabrication of personalized implants, organ-on-chips, and organoids. And we look forward to the frontier direction of 3D bioprinting in the next stage, putting forward our views on the medical applications of 3D-bioprinted functional tissues and organs.